[Ideas and Briefing about Regulatory Requirements for Laboratory Developed Tests in the US]

As a special kind of in vitro diagnostic devices（IVDs）, laboratory developed tests（LDTs） are of great significance to the development of clinical laboratories. This study aims to explore the regulatory requirements ideas of LDTs. By introducing the development of LDTs and the changing of regulatory requirements in the United States, combing the current regulatory framework and discussing relevant ideas in the regulatory requirements of LDTs.

Companion Diagnostics: State of the Art and New Regulations

Companion diagnostics (CDx) hail promise of improving the drug development process and precision medicine. However, there are various challenges involved in the clinical development and regulation of CDx, which are considered high-risk in vitro diagnostic medical devices given the role they play in therapeutic decision-making and the complications they may introduce with respect to their sensitivity and specificity. The European Union (E.U.) is currently in the process of bringing into effect in vitro Diagnostic Medical Devices Regulation (IVDR). The new Regulation is introducing a wide range of stringent requirements for scientific validity, analytical and clinical performance, as well as on post-market surveillance activities throughout the lifetime of in vitro diagnostics (IVD). Compliance with General Safety and Performance Requirements (GSPRs) adopts a risk-based approach, which is also the case for the new classification system. This changing regulatory framework has an impact on all stakeholders involved in the IVD Industry, including Authorized Representatives, Distributors, Importers, Notified Bodies, and Reference Laboratories and is expected to have a significant effect on the development of new CDx.

Modifying laboratory testing via home brew during the COVID-19 pandemic

Rapid development and deployment of diagnostic testing for COVID-19 have been a key component of the public health response to the pandemic. Out of necessity, academic and other clinical laboratories developed laboratory testing innovations for COVID-19 to meet clinical testing demands. In addition to constraints on local testing supplies and equipment, a rapidly changing regulatory framework created challenges for translational scientists. Illustrative examples of approaches used to develop laboratory tests during the early stages of the COVID-19 pandemic demonstrate effective team science approaches to this challenging clinical care and public health emergency. These experiences and the associated lessons learned are relevant to the development of public health response plans for future pandemics.

Programmed death ligand 1 immunohistochemistry in non-small cell lung carcinoma

Lung cancer is the leading cause of cancer death worldwide with low response rates to conventional chemotherapy. New promising therapies have emerged based on programmed cell death protein 1 (PD-1) immunity checkpoint inhibitors (ICI), including anti-PD-1, such as nivolumab and pembrolizumab, or programmed death ligand 1 (PD-L1) inhibitors, such as atezolizumab, durvalumab, and avelumab. The prescription of pembrolizumab has been approved by FDA and EMA for advanced stages non-small cell lung carcinoma (NSCLC), restricted for first-line setting to patients whose tumor presents ≥50% of PD-L1 positive tumor cells (TC), and ≥1% for second-line and beyond, leading to consider PD-L1 assay as a companion diagnostic tool for pembrolizumab. Very recently, the EMA has approved durvalumab for the treatment of patients with unresectable stage III NSCLC not progressing after chemoradiotherapy and whose tumors express PD-L1 on ≥1% of TC. Four standardized PD-L1 immunohistochemistry assays have been used in clinical trials; 22C3 and 28-8 PharmDx assays on Dako/Agilent platforms, and SP142 and SP263 assays on Ventana platforms, each test having been developed initially for a specific ICI. They differ in terms of primary monoclonal antibody, platform, detection system and scoring methods with different thresholds of positivity validated in clinical trials. Several studies have shown a close analytical performance of the 22C3, 28-8 and SP263 assays regarding TC staining in NSCLC, with poor concordance with SP142 assay and for immune cells. However, as dedicated platforms are not available in all pathology laboratories and because of the high cost of these assays, laboratory developed tests are widely used in many countries. Their validation must guarantee the same sensitivities and specificities as compared to standardized assays. Overall, PD-L1 test is of great help to select patients who could benefit for ICI and most pathologists have included this test in their daily practice for advanced stages NSCLC, besides ALK and ROS1 IHC.

Direct-to-Consumer Genetic Testing: Finding a Clear Path Forward

Regulatory compliance in the direct-to-consumer genetic testing market is highly sophisticated as there are numerous federal, state, and ethical barriers to entry. In 2010, amid an underregulated market, 23andMe sought to do what few companies in the medical industry had attempted before-disregard the guidance and requests of the US Food and Drug Administration. This regulatory strategy effectively destined the company's Personal Genome Service for failure; however, the company changed course and has been granted several regulatory clearances. This exemplifies the importance of a healthy relationship with regulatory agencies, although challenges remain. The DTC industry continues to have a perplexing regulatory framework at both the federal and state level. There are also ethical concerns with the monetization of deidentified genetic health information, as genetic data have an inherent level of identifiability and are not fully protected by the Health Insurance Portability and Accountability Act (HIPAA) Privacy Rule in these scenarios. Although some DTC tests are now cleared in the United States, the concern that a learned intermediary is needed for interpretation of results remains. The regulatory oversight of this market will need to continue to develop to ensure the protection of consumer health and privacy.